Bool remove from array by value

feilara (2)
Was recently tasked with removing all instances of a value from an array with a boolean function. I have it working but was wondering if there was any way to write it better/optimize it, here is what I have:

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  bool deleteValue(int list[], int target, int &size)
{
        // log original array size to see if it has changed
        const int originalSize = size;

        // search target in array
        int i;
        for (i = 0; i < size; i ++)
        {
                if (list[i] == target)
                {
                        // if target found in array
                        if (i < size)
                        {
                                // reduce the size of array and move all elements one space ahead
                                size = size - 1;
                                for (int j = i; j < size; j ++)
                                {
                                        list[j] = list[j + 1];
                                }
                        }
                }
        }

        if (originalSize == size)
        {
                return false;
        }

}


Would love to know if it could be improved upon.

The output should look like this:
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11
 
Original array
[ 11, 2, 27, 34, 31, 78, 67, 91, 86, 10 ]

Target value 0 for removal is NOT in the list.
[ 11, 2, 27, 34, 31, 78, 67, 91, 86, 10 ]

Original array
[ 2, 63, 0, 56, 74, 44, 65, 0, 93, 68 ]

Target value: 0 is removed from the list.
[ 2, 63, 56, 74, 44, 65, 93, 68 ]
salem c (3715)
feilara (2)
Had to implement it without helper functions, so no remove_it
dhayden (5799)
Yes, it can be improved. Instead of copying the entire remaining array each time you delete one item, you should copy each item only once. For this problem, I find it easiest to keep two variables: one for the source item and once for the destination:
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bool deleteValue(int list[], int target, int &size)
{
        // log original array size to see if it has changed
        const int originalSize = size;

        // search target in array
        int src=0, dst=0;
        for (src = 0; src < size; src++) {
            if (list[src] == target) {
                cout << "Skip idx " << src << '\n';
                // Do nothing
            } else if (src != dst) {
                // You've already skipped something, so copy this one
                list[dst++] = list[src];
            } else {
                dst++;
            }
        }
        size = dst;
        return (originalSize != size);
}


Also, there are functions in the standard library to do this, but I assume that you're doing this as a learning experience.
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